Pneumatic dispatch tube system



Dec. 22, 1931. J. T. COWLEY PNEUMATIC DISPATCH TUBE SYSTEM 5 Sheets-Sheet Filed Sept. 30, 1929 a 7 s1 t \NOW. t \w .A\\\ t 0 A "C 3 w h m 4P m CCt (I12 4 3 3 2 w 3 g m H mm Dec. 22, 1931. J. T. COWLEY PNEUMATIC DISPATCH TUBE SYSTEM Filed Sept. 50, 1929 3 Sheets-Sheet 2 Inventor James T Cowley Dec. 22, 1931.

Filed Sept. 30, 1929 J. T. COWLEY PNEUMATIC DISPATCH TUBE SYSTEM 3 Sheets-Sheet 1 James 1' Cawly Patented Dec. 22, 1931 UNITED STATES PATENT oFFic JAMES '1". COWLEY, OF SYRACUSE, NEW YORK, ASSIG-NOR TO THE LAMSON COIVIZPANY, I V

F SYRACUSE, NEW YORK, A CORPORATION OF MASSACHUSETTS PNEUMATIC DISPATCH TUBE sYsrEM 1 Application filed September 30, 1929. Serial No. 396,083.

This invention relates to an improvement in pneumatic dispatch tube system of the minimum flow type. In such a system the transmission tube is supplied with power through a continuation ofthe tube which leads to a source of negative pressure, such for example as a vacuum drum or header. The vacuum pressure in the transmission tube is regulated by a valve located in such continuation tube, and it has heretofore been the practice to provide a power control which operates directly upon such valve in response to the various conditions set up in the transmission tube. Such practice renders it necessary to provide a power control element especially constructed for each size of tube.

The primary object of this invention is to provide a separate power control unit which may be attached to continuation tubes of various diameters for opening and closing the valves in the tubes. I

Other objects will appear from a consideration of the following specification taken p rod or stem 30hav1ng a reduced end portion 31 which passes through an aperture 82in in connection with the drawings which form a art thereof, and in which:

ig. 1 is a plan view of a portion of a continuation tube provided with a power control unit- F i g. 2 is a sectional view taken along the line 2-2 of Fig. 1;

Fig. 3 is a side elevation of the construction shown in Figs. 1 and 2, the relation of the valves of the tube and unit being indicated by dotted lines; and

Figs. 4 and 5 are sectional views illustrating the power control unit with the valve in opened and closed positions.

In the drawings the reference numeral 1Q designates a tube which forms a continuation of the transmission tube, not shown, connecting it to the source of negative power, also not shown. The tube 10 has an axially exending passage 11 in which is mounted a valve 12 of the butterfly type carried on a shaft 13. bosses 14 on the tube with its ends projecting beyond the bosses for reasons to be pointed out below. In one wall of the tube 10, above and below the valve 12, are provided orifices 15 and 16.

The shaft 13 is supported in.

and 16 inthe wall 'of the tube 10. The ele- 'ment 21 may be briefly-described as comprising a tube 25 having an axial passage in WlllCil'lS mounted a Valvev 26carried by a shaft 27; The position" of the valve26. is

controlledby a plurality of pneumatics 28, 29. the term pneumatic it will be understood that I designate broadly, any

pressure or vacuum instrumentality, such as for instance a flexible diaphragm, piston, or

bellows by which fluid pressure lsconverted into mechanioalmotion. I

The pneumatic 28' acts to reciprocate a the valve 26. The difference in diameter be- I tween the two portions of the stem 30 pro vides a shoulder 38, and mounted upon the reducedportion 31 is a collar 34. The shoulder and collar are, as is clearly shown] in Figs. 4 and 5, on opposite sides of the valve 26. The shoulder 33 acts, when hepneumatic28 is in oneposition, to initiate the opening of the valve as shown in Fig. i and the-co1lar34 acts, w-henthe pneumatic 28 is in the other position, to initiate the closing ofthe valve 26. The pneumatic 29 operates a rod 35 carryinga valve 36 which'controls .a 'port- 37 connecting the housing .of the pneumatic-28 with the passage in the tube 2.5.. A by-pass 38 controlled by a screw :59 acts with the aperture 32 to provide a continuous minimum flow of air through the passage without disturbing the pneumatics whichnormally assume the positions shown. in Fig.5. Y

The shafts 27 and 18 are preferably though not necessarily in axial alignment. Mounted upon the end of the shaft 27 adjacent the tube 10, is'an arm 40 having at its outwardly projecting bar 43.

upper end a notch or recess 41. Mounted upon the end of the shaft 13 adjacent the tube 25 is an arm 42 which terminates in an The bar 43 enters the notch 41 in the arm 40 and since tube 21, provide passages through which,

' the port 37.

when. the valve 12 is closed, as shown in Fig. 3, air is bypassed from the tube through the tube 21'. The air passes into the tube 25 from the tube 10 through the orifice 1'5 and conduit 22, through the aperture 32 and port 88 into the conduit 23 and thence, through the'orifice 16 into the tube 10 below the valve. When, however, a carrier is inserted into the'transmission line, the minimum fiow'is substantially cutoff sothat the pressure of air in the'system is reduced. This reduction of the pressure acts through the port 37 upon the pneumatic 28, causing it to shift from the position shown in Fig. 5 to that shown in Fig. 4. The pneumatic 29 then shifts into. the F ig; 4 position closing matic 28 causes the shoulder 33 of the stem to bear against one face of thevalve 26 shifting it from its closed position. The air rushing' through the tube 21 completes the opening of the valve. By reason of the con nection between the shaft 27 of the valve 26' and the shaft v13 of the valve 12, this movementof the valve 26 causes the valve 12 to 7 open, thusproviding a free passage for the air through the tube 10 and permitting the creation of the necessary pressure in the 1 12 will be automatically reopened as pointed out above- The'amount of play provided between the bar 43 and notch'41 permits the 'valve 12 to start to open and to resume its seat afterthe valve 26. 'This eliminates the necessity for extreme care in adjusting the operation of such valves. Moreover the opening of the valve 26 is largely performed by the rush of air after the initiation of such movement and thus more power is provided to move the valve 12- from its closed posi- This movement of the pneution than would be the case if the valves moved simultaneously.

The 7 construction above. described and shown in the drawings thus provides in combination with the valved continuation tube of a minimum flow pneumatic dispatch system a controlunit by which the valve'of the tube is caused to move in 'response to the status of the air in the transmission line. Moreover the unit may be employed with tubes of various diameters so that it can be -withthe continuation tube thereof having a valvetherein, of a control unit responsive to the status of the air 111' the 'transmls'sion line including a valve, 'andmeans positively actuated by the valve in the unit for opening.

or closing the valvein the continuationtube.

2. In a pneumatic dispatch." tube apparatus'of the minimum flow type, thecombination with the continuation tube'thereof having ayva'lve therein,-of a control unit responsive to the status of the airin the trans mission line, a'valve in said unitand means connecting said valves whereby the opening and closing'of thevalveinthe unit causes this) opening and closing of thevalve in the tue.

3. In a pneumatic dispatch tube appara *tus of the minimum flow type, the combination with the continuation tube thereof havmg a valve therein, ofa control unit responslve to the status of the air in the transmis sion line, a valve in said unit and a connection between saidvalves, which connection provides considerable play whereby the valve in the continuation tube is opened-and closed after the valve in the unit is opened and closed. I 4. In a pneumatic dispatch tube appara tus of the minimum flow type, the combination with'the continuation tube thereof having a valve therein, of'a control unit responsive to the status of the air in the transmission line, a valve in said unit and a connection between said valves, whereby the'va'lve in the continuation tube is opened andclosed after the valve inthe unit is opened and closed.

5. In a pneumatic dispatch tube apparatus of the minimum flow type, the combination.

with the continuation tube thereof having a valve therein, of a control unit responsive to the status of the air in the transmission line,

a valve in said unit, conduits connecting said unit and tube above and below the valves therein, means in the unit providing a bypass around its valve whereby said unit acts as a bypass when the valve in the tube is closed, the valve in the unit opening and closing in response to the status of the air and means causing the valve in the unit to open and close the valve in the tube.

6. In a pneumatic dispatch tube apparatus of the minimum flow type, the combina tion with the continuation tube thereof having a valve therein, of a control unit responsive to the status of the air in the transmission line, a valve in said unit, conduits connecting said unit and tube above and below the valves therein, means in the unit providing a bypass around its valve whereby said unit acts as a bypass when the valve in the tube is closed, the valve in the unit opening and closing in response to the status of the air, means for initiating the opening and closing movements of the valve in the unit and a connection between the valves causing the valve in the unit to open and close the valve in the tube.

7. In a pneumatic dispatch tube apparatus of the minimum flow type, the combination with the continuation tube thereof having a valve therein, of a control unit responsive to the status of the air in the transmission line, a valve in said unit, conduits connecting said unit and tube above and below the valves therein, means in the unit providing a bypass around its valve whereby said unit acts as a bypass when the valve in the tube is closed, the valve in the unit opening and closing in response to the status of the air, pneumatic means for initiating the opening and closing movements of the valve in the unit and a connection between the valves causing the valve in the unit to open and close the valve in the tube.

8. In a pneumatic dispatch tube apparatus of the minimum flow type, the combination with the continuation tube thereof, a transversely extending shaft in said tube and a valve upon said shaft, of a control unit responsive to the status of the air in the transmission line, said unit having a passage therethrough, conduits connecting said passage with the tube above and below the valve therein whereby the passage acts as a bypass when the valve is closed, automatically acting means for controlling the flow of air through said bypass and a connection from said means to said valve for opening said valve when said bypass is open and closing said valve when said bypass is restricted.

9. In a pneumatic dispatchtube apparatus of the minimum flow type, the combination with the continuation tube thereof, a transversely extending shaft in said tube and a valve upon said shaft, of a control unit responsive to the status of the air in the transmission line, said unit having a passage therethrough, conduits connecting said pas sage with the tube above and belowthe valve.

Signed by me at Boston, Massachusetts,

this 27th day of September, 1929.

JAMES T. COWLEY. 

